In the control and monitoring of a modern food factory, there is a need for the rapid analysis of several parameters of the raw materials and the final product such as protein and fat content, moisture and colour. Historically, such measurements have been carried out batchwise in a laboratory using conventional physical and chemical techniques and these take many hours or even days to complete. The raw materials and food products analysed can include milk powders, egg products, wheat, flour, cake mixes, starches and other farinaceous products.
Over the past few years, modern technology has provided instruments that have gone some way to providing the rapid analysis required. Examples of such instruments are various forms of spectrometer, for example, a reflectance spectrometer. These instruments are non-destructive on the sample and depend on irradiating the sample with waves of a particular frequency and measuring the reflected radiation which may be attenuated according to the characteristics of the sample under test. An example of such an instrument is a Near Infra-Red Reflectance Spectrometer (hereinafter called "N.I.R.").
When such instruments are used in the laboratory to test samples of particulate food materials, careful packing and cleaning of the sample cell is of paramount importance as surface imperfections and carry-over of one sample to another lead to unreliable results. In addition to sample preparation, there is still the onerous task of sampling reliably both raw material and product at regular intervals to obtain a representative picture of their composition.